Fast algorithms for shortest paths in planar graphs, with applications
SIAM Journal on Computing
The input/output complexity of sorting and related problems
Communications of the ACM
Proceedings of the seventeenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Special Interest Group on Management of Data (SIGMOD)/Principles of Data Base Systems (PODS)
The art of computer programming, volume 3: (2nd ed.) sorting and searching
The art of computer programming, volume 3: (2nd ed.) sorting and searching
External-memory graph algorithms
Proceedings of the sixth annual ACM-SIAM symposium on Discrete algorithms
I/O-efficient algorithms for contour-line extraction and planar graph blocking
Proceedings of the ninth annual ACM-SIAM symposium on Discrete algorithms
I/O-complexity of graph algorithms
Proceedings of the tenth annual ACM-SIAM symposium on Discrete algorithms
On external memory graph traversal
SODA '00 Proceedings of the eleventh annual ACM-SIAM symposium on Discrete algorithms
Worst-Case External-Memory Priority Queues
SWAT '98 Proceedings of the 6th Scandinavian Workshop on Algorithm Theory
The Buffer Tree: A New Technique for Optimal I/O-Algorithms (Extended Abstract)
WADS '95 Proceedings of the 4th International Workshop on Algorithms and Data Structures
External Memory Algorithms for Outerplanar Graphs
ISAAC '99 Proceedings of the 10th International Symposium on Algorithms and Computation
Memory Paging for Connectivity and Path Problems in Graphs
ISAAC '93 Proceedings of the 4th International Symposium on Algorithms and Computation
The I/O - Complexity of Ordered Binary - Decision Diagram Manipulation
ISAAC '95 Proceedings of the 6th International Symposium on Algorithms and Computation
Improved Algorithms and Data Structures for Solving Graph Problems in External Memory
SPDP '96 Proceedings of the 8th IEEE Symposium on Parallel and Distributed Processing (SPDP '96)
An external memory data structure for shortest path queries (extended abstract)
COCOON'99 Proceedings of the 5th annual international conference on Computing and combinatorics
On external-memory MST, SSSP and multi-way planar graph separation
Journal of Algorithms
External-memory depth-first search algorithm for solid grid graphs
Information Processing Letters
Statistical Models for Empirical Search-Based Performance Tuning
International Journal of High Performance Computing Applications
Proceedings of the 2006 ACM symposium on Applied computing
An external-memory depth-first search algorithm for general grid graphs
Theoretical Computer Science
TerraStream: from elevation data to watershed hierarchies
Proceedings of the 15th annual ACM international symposium on Advances in geographic information systems
Terracost: Computing least-cost-path surfaces for massive grid terrains
Journal of Experimental Algorithmics (JEA)
Computing visibility on terrains in external memory
Journal of Experimental Algorithmics (JEA)
External-memory depth-first search algorithm for solid grid graphs
Information Processing Letters
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The potential and use of Geographic Information Systems is rapidly increasing due to the increasing availability of massive amounts of geospatial data from projects like NASA's Mission to Planet Earth. However, the use of these massive datasets also exposes scalability problems with existing GIS algorithms. These scalability problems are mainly due to the fact that most GIS algorithms have been designed to minimize internal computation time, while I/O communication often is the bottleneck when processing massive amounts of data. In this paper, we consider I/O-efficient algorithms for problems on grid-based terrains.Detailed grid-based terrain data is rapidly becoming available for much of the earth's surface. We describe [EQUATION] I/O algorithms for several problems on [EQUATION] grids for which only O(N) algorithms were previously known. Here M denotes the size of the main memory and B the size of a disk block.We demonstrate the practical merits of our work by comparing the empirical performance of our new algorithm for the flow accumulation problem with that of the previously best known algorithm. Flow accumulation, which models flow of water through a terrain, is one of the most basic hydrologic attributes of a terrain. We present the results of an extensive set of experiments on real-life terrain datasets of different sizes and characteristics. Our experiments show that while our new algorithm scales nicely with dataset size, the previously known algorithm "breaks down" once the size of the dataset becomes bigger than the available main memory. For example, while our algorithm computes the flow accumulation for the Appalachian Mountains in about three hours, the previously known algorithm takes several weeks.